The invention relates to universal holonomic transmissions with a non-stepwise change of torque and could be utilized in engineering industry, vehicles, machine-tool industry and other objects and systems wherein an automatic or forced smooth change of an output (driven) shaft rotational speed is utilized depending on its load torque with a constant or variable input (driving) shaft rotational speed. The transmission could be utilized in rolling mills, drilling rigs, for adaptation of railways to electric traction on alternating current.
A transmission with a friction variable-speed drive disclosed in Pronin B. A., Revkov G. A. xe2x80x9cNon-stepwise V-belt and friction transmissionsxe2x80x9d. Moscow, xe2x80x9cMashinostroeniexe2x80x9d, 1980, p. 290, FIG. 178. ( .A., xcex93.A. xe2x80x9c       xe2x80x9d. M.: xe2x80x9c xe2x80x9d, 1980, c. 290, . 178) is known.
The disadvantages of the known technical solution are as follows: great pressures onto shafts and bearings, which pressures being associated with utilizing the frictional forces to transmit a moment; a non-rigidity of the transmission characteristic; a short longevity and low efficiency due to a slippage in contact zones; limitations on power being transmitted.
A closest analogue to the proposed construction by its technical essence is a universal holonomic transmission with a non-stepwise change of torque, the transmission including: an output shaft; a shaft intended for connecting with external devices; and an input shaft coupled with the latter shaft; planetary transmission satellites are fixed on two sides relatively to the input shaft on axes mounted free on the input shaft, the satellites placed from one side of the input shaft being connected with a gear wheel fixed on an epicycle of a differential gear comprising a carrier on which axes the satellites coupling the epicycle and a sun wheel are mounted, the sun wheel being fixed on the shaft intended for connecting with external devices, and the planetary transmission satellites placed from the other side of the input shaft are kinematically connected with the output shaft (Russian Patent No 2,053,895, Int. Cl. B 60 K 17/12, 1993).
The proposed construction comprises a second differential gear connected with the first one by the planetary transmission with a defined transmission ratio.
The disadvantages of the known construction are as follows:
a necessity of a constant gear engagement both on input and output shafts, thereby substantially lowering the transmission efficiency;
an occurrence of additional transmission losses at the cost of the fact that in the direct transmission mode all tansmission members are stopped relative to their axes and each other, i.e., as if a continuous shaft is established.
However, the input shaft and the differential gear carrier rigidly placed on one shaft revolve around the sun gears and rotate with the speed few less than the drive and output shaft rotational speeds (which are equal in the direct transmission mode).
Technical problems being solved by proposed universal holonomic transmission with a non-stepwise change of torque arc:
to simplify the transmission construction due to excluding the differential gear on the output shaft;
to provide obtaining the output shaft rotational speed faster than the input shaft rotational speed, since at the moment this is obtained by utilizing one or more additional transmissions;
to provide a possibility of non-stepwise change of the gear ratios both automatically and forcedly.
The technical result in the proposed construction is obtained by creating a universal holonomic transmission with a non-stepwise change of torque, said transmission including: an output shaft; a shaft intended for connecting with external devices; and an input shaft coupled with the latter shaft; planetary transmission satellites are fixed on two sides relatively to the input shaft on axes mounted free on the input shaft, the satellites placed from one side of the input shaft being connected with a gear wheel fixed on an epicycle of a differential gear comprising a carrier on which axes the satellites coupling the epicycle and a sun wheel are mounted, the sun wheel being fixed on the shaft intended for connecting with external devices, and the planetary transmission satellites placed from the other side of the input shaft are kinematically connected with the output shaft; wherein, in accordance with the invention, the input shaft is mounted as a rotatable one relative to the output shaft, an additional gear wheel and the differential gear carrier being fixed on the output shaft, which additional gear wheel comes into engagement with the planetary transmission satellites placed from the other side of the input shaft.
Another variant of embodiment of the proposed construction is a universal holonomic transmission with a non-stepwise change of torque, the transmission including: an output shaft; a shaft intended for connecting with external devices; and an input shaft coupled with the latter shaft; planetary transmission satellites are fixed on two sides relatively to the input shaft on axes mounted free on the input shaft, the satellites placed from one side of the input shaft being connected with a gear wheel, and a differential gear having an epicycle, a carrier on which axes the satellites connecting the epicycle and a sun wheel are mounted, which differential gear is kinematically connected with the shaft intended for connecting with external devices, and the planetary transmission satellites placed from the other side of the input shaft are kinematically connected with the output shaft; wherein, in accordance with the invention, the input shaft is mounted as a rotatable one relative to the output shaft, and two gear wheels are fixed on the output shaft, one of which gear wheels, an additional one, is connected with the planetary transmission satellites placed from the other side of the input shaft, and the second wheel is the sun wheel of the differential gear, the epicycle of the differential gear being fixed on the shaft intended for connecting with external devices and the gear wheel being fixed on the carrier.
The proposed transmission is compact, has no limitations on the power being transmitted and on rotational speed.
A wide range of gear ratios obtained by the transmission allows to organize an operation mode of mechanisms in which the proposed transmission is utilized according to the characteristic of minimum fuel rates.
The proposed holonomic transmission with a non-stepwise change of torque is a progressive variable-speed drive, i.e., when utilizing it in vehicles, the following equation is true:
Mi*xcfx891=NABC=const, and a change of transmission gear ratios occurs automatically and depends on vehicles dynamics and path profile, when NABC=const.